Hello,
I am using some leftover led’s for a sign and was wondering what is the best way to control a 12v single color analog strip with WLED that is also controlling a 5v strip, specifically best practices with wiring.
Wiring best practices are typically about using large enough wire to handle the total current required.
Analog setups need MOSFETs for each channel (R,G,B) and a pin to drive them, so a total of 3 more GPIOs must be available on your controller.
Other than that, you’ll need separate 12V and 5V supplies that can handle the total current needed for each voltage. You may be able to use a single 12V supply and add 12V->5V buck converter(s) for your 5V needs.
If you can describe your setup in more detail, we can give more suggestions.